Topic outline

  • GPS Surveying - Differential or Relative Positioning

    Credits: 2 PDH

    PDH Course Description:

    Differential GPS positioning is simply a process of determining the relative differences in coordinates between two receiver points, each of which is simultaneously observing/measuring satellite code ranges and/or carrier phases from the GPS satellite constellation. These differential observations, in effect, derive a differential baseline vector between the two points. This method will position two stations relative to each other, hence the term "relative positioning", and can provide the higher accuracies required for project control surveys, topographic surveys, and hydrographic surveys. There are basically two general types of differential positioning: Code phase pseudorange tracking and Carrier phase tracking.

    Topics:

    • Differential Positioning Concepts
    • Differential Positioning (Code Pseudorange Tracking)
    • Differential Positioning (Carrier Phase Tracking)
    • Carrier Phase Survey Techniques
    • Real-time Kinematic (RTK) GPS
    • Differential GPS Accuracies
    • Differential GPS Augmentation Systems
    • Maritime Differential GPS (MDGPS)
    • Nationwide Differential GPS (NDGPS)
    • FAA Wide Area Augmentation System (WAAS)
    • FAA Local Area Augmentation System (LAAS)
    • The National Continuously Operating Reference Station (CORS) System

    To take this course:

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    2.) Study: Once enrolled, click below to begin the course:

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    3.) Test: Once you've thoroughly read the course materials, please click below to take the final examination.

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    4.) Certificate: A passing grade of 70% or higher on the exam, is required to receive the certificate of completion for this PDH course.


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    Intended Audience: This course is intended for surveying and engineering professionals whose job description may require an intermediate knowledge of GPS practices and principles.

    Publication Source: USACE (Corp of Engineers)

    Donald Parnell, PE